Construction problems of volume protected by airtermination rod for the ukrainian nuclear power plant under standard EN 62305
Mathematical analysis of the rolling sphere method was performed to develop a model for constructing of volume protected by rod air-termination in accordance with EN 62305:2012 for the protection of nuclear power plants objects from direct lightning strike. The necessity of development of the corres...
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| Zitieren: | Construction problems of volume protected by airtermination rod for the ukrainian nuclear power plant under standard EN 62305 / О.Ye. Istomin, D.G. Koliushko, S.V. Kiprych, S.S. Rudenko // Problems of atomic science and technology. — 2019. — № 5. — С. 100-104. — Бібліогр.: 8 назв. — англ. |
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irk-123456789-1952252023-12-03T17:36:39Z Construction problems of volume protected by airtermination rod for the ukrainian nuclear power plant under standard EN 62305 Istomin, О.Ye. Koliushko, D.G. Kiprych, S.V. Rudenko, S.S. Problems of modern nuclear power engineering Mathematical analysis of the rolling sphere method was performed to develop a model for constructing of volume protected by rod air-termination in accordance with EN 62305:2012 for the protection of nuclear power plants objects from direct lightning strike. The necessity of development of the corresponding mathematical model for similar objects is shown, and the direction of its realization with the help of decomposition method is proposed. The mathematical models for calculation of protection zones of single and double air-termination rods of arbitrary height and location are developed. Directions of further researches are formed. Виконано математичний аналіз методу сфери, що котиться, для розробки моделі побудови зон захисту складної системи блискавковідводів згідно з ДСТУ EN 62305:2012 для захисту об’єктів атомних електричних станцій від прямого удару блискавки. Показана необхідність розробки відповідної математичної моделі для подібних об’єктів та запропоновано напрямок її реалізації за допомогою методу декомпозиції. Розроблено математичні моделі для розрахунку зон захисту одиничного та подвійного стрижньових блискавковідводів довільної висоти і розташування. Сформовано напрями подальших досліджень. Выполнен математический анализ метода катящейся сферы, для разработки модели построения зон защиты сложной системы молниеотводов согласно ДСТУ EN 62305: 2012 для защиты объектов атомных электрических станций от прямого удара молнии. Показана необходимость разработки соответствующей математической модели для подобных объектов и предложены направление реализации с помощью метода декомпозиции. Разработаны математические модели для расчета зон защиты одиночного и двойного стержневых молниеотводов произвольной высоты и расположения. Сформированы направления для дальнейших исследований. 2019 Article Construction problems of volume protected by airtermination rod for the ukrainian nuclear power plant under standard EN 62305 / О.Ye. Istomin, D.G. Koliushko, S.V. Kiprych, S.S. Rudenko // Problems of atomic science and technology. — 2019. — № 5. — С. 100-104. — Бібліогр.: 8 назв. — англ. 1562-6016 PACS: 28.90.+i http://dspace.nbuv.gov.ua/handle/123456789/195225 en Вопросы атомной науки и техники Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
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Problems of modern nuclear power engineering Problems of modern nuclear power engineering |
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Problems of modern nuclear power engineering Problems of modern nuclear power engineering Istomin, О.Ye. Koliushko, D.G. Kiprych, S.V. Rudenko, S.S. Construction problems of volume protected by airtermination rod for the ukrainian nuclear power plant under standard EN 62305 Вопросы атомной науки и техники |
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Mathematical analysis of the rolling sphere method was performed to develop a model for constructing of volume protected by rod air-termination in accordance with EN 62305:2012 for the protection of nuclear power plants objects from direct lightning strike. The necessity of development of the corresponding mathematical model for similar objects is shown, and the direction of its realization with the help of decomposition method is proposed. The mathematical models for calculation of protection zones of single and double air-termination rods of arbitrary height and location are developed. Directions of further researches are formed. |
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| author |
Istomin, О.Ye. Koliushko, D.G. Kiprych, S.V. Rudenko, S.S. |
| author_facet |
Istomin, О.Ye. Koliushko, D.G. Kiprych, S.V. Rudenko, S.S. |
| author_sort |
Istomin, О.Ye. |
| title |
Construction problems of volume protected by airtermination rod for the ukrainian nuclear power plant under standard EN 62305 |
| title_short |
Construction problems of volume protected by airtermination rod for the ukrainian nuclear power plant under standard EN 62305 |
| title_full |
Construction problems of volume protected by airtermination rod for the ukrainian nuclear power plant under standard EN 62305 |
| title_fullStr |
Construction problems of volume protected by airtermination rod for the ukrainian nuclear power plant under standard EN 62305 |
| title_full_unstemmed |
Construction problems of volume protected by airtermination rod for the ukrainian nuclear power plant under standard EN 62305 |
| title_sort |
construction problems of volume protected by airtermination rod for the ukrainian nuclear power plant under standard en 62305 |
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Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
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2019 |
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Problems of modern nuclear power engineering |
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http://dspace.nbuv.gov.ua/handle/123456789/195225 |
| citation_txt |
Construction problems of volume protected by airtermination rod for the ukrainian nuclear power plant under standard EN 62305 / О.Ye. Istomin, D.G. Koliushko, S.V. Kiprych, S.S. Rudenko // Problems of atomic science and technology. — 2019. — № 5. — С. 100-104. — Бібліогр.: 8 назв. — англ. |
| series |
Вопросы атомной науки и техники |
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2025-07-16T23:05:42Z |
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| fulltext |
ISSN 1562-6016. PASТ. 2019. №5(123), p. 100-104.
CONSTRUCTION PROBLEMS OF VOLUME PROTECTED BY AIR-
TERMINATION ROD FOR THE UKRAINIAN NUCLEAR POWER
PLANT UNDER STANDARD EN 62305
О.Ye. Istomin, D.G. Koliushko, S.V. Kiprych, S.S. Rudenko
National Technical University “Kharkiv Polytechnical Institute”, Kharkiv, Ukraine
E-mail: nio5_molniya@ukr.net
Mathematical analysis of the rolling sphere method was performed to develop a model for constructing of
volume protected by rod air-termination in accordance with EN 62305:2012 for the protection of nuclear power
plants objects from direct lightning strike. The necessity of development of the corresponding mathematical model
for similar objects is shown, and the direction of its realization with the help of decomposition method is proposed.
The mathematical models for calculation of protection zones of single and double air-termination rods of arbitrary
height and location are developed. Directions of further researches are formed.
PACS: 28.90.+i
PROBLEM FORMULATION
The lightning protection system at nuclear power
plant (NPP) is a complicated configuration system with
multiple air-termination rods (ATR) and catenary wires,
as well as protective grids installed on roofs of
buildings. The main purpose of the lightning protection
system at the NPP is to protect against direct lightning
strike to ensure the safety of the personnel, the
reliability of the equipment operation and the protection
of expensive microprocessor equipment in the control
system of technological processes. The failure of the
NPP equipment due to a direct lightning strike can lead
to a current defeat of service staff, significant material
damage due to violation of technological processes,
downtime of equipment, etc. In addition, the relevance
of lightning protection of such objects increases in
comparison with objects of a small area, in connection
with the increase of thunderstorm activity for the
branched system of lightning protection [1].
Lightning protection systems of the vast majority of
strategic energy objects of Ukraine, including NPP, are
designed in accordance with the standards requirements
of the former USSR. Consequently there is a need for its
verification and modernization according to the
requirements of existing normative documents [2, 3].
Authors from 2007 to 2018 have conducted the
diagnostics and developed recommendations for the
reconstruction of the lightning protection system in
accordance with the requirements [2] for a number of
power units, buildings and constructions of all operating
NPP of Ukraine and an open switchgear with a voltage
class of 750 kV of one NPP.
At present, Ukraine has two normative documents in
the field of lightning protection of buildings and
constructions:
– DSTU B V.2.5-38:2008 Engineering equipment of
buildings and constructions. Arrangement of lightning
protection of buildings and constructions [2];
– EN 62305-3:2011, IDT Protection against
lightning – Part 3: Physical damage to structures and
life hazard [3].
The harmonized international lightning protection
standard [3] foresees the calculation of protection zone
(PZ) of ATR from a direct lightning strike using two
methods: a protective angle and rolling sphere.
However, the protective angle method according to [3]
is acceptable only for buildings of simple shape and has
a limit on the height of ATR. Therefore, only the rolling
sphere method can be used to calculate the PZ of ATR
system of NPP from a direct lightning strike and their
open switchgear. It has more stringent requirements for
ATR protection zones than DSTU B V.2.5-38:2008 [2]:
PZ of the single ATR with a damage probability of 10%
decreases from 55 to 45 m, and the calculation of
lightning protection systems on its basis reduces the
probability of lightning damage of the object to be
protected. However, engineering techniques of using the
rolling sphere method are absent in [3], making its
practical application impossible. This leads to the fact
that neither lightning protection designers nor NPP
operational staff can assess the security of such
strategically important objects from direct lightning
strike.
The advantages and disadvantages of the existing
methods for calculating the PZ ATR and the absence of
the necessary mathematical apparatus for calculating the
PZ of multiple ATRs are indicated in [4]. The
mathematical relationships given in [5–7] for specific
cases of ATR location cannot be used to calculate the
protection of the complex of buildings and constructions
from a lightning strike by the ATR system. In particular,
in [5] formulas are given for determining the
coordinates of the fictitious sphere center, according to
which the sizes of PZ for two ATRs of different heights
are uniquely determined, but both ATRs have heights
less than the radius of the fictitious sphere. In [6], a
number of examples of PZ, constructed by the rolling
sphere method, are presented. An algorithm has been
developed for constructing the PZ for an arbitrary
number of ATRs using the MATLAB software.
However, presented expressions and the algorithm make
it possible to determine the PZ only in the case of
equally high ATRs, the coincidence with which in real
life is possible with a rather low probability. That is,
only parametric examples, and not general ones, are
provided.
In [8], an algorithm was proposed for determining
the ATR PZ to protect substation equipment from a
direct lightning strike. The expressions for single and
double ATRs are obtained, as well the geometric
solution of this problem is considered in detail.
Examples of the PZ construction for a system of four
ATR are presented. However, the work presents cases
of only equally high ATRs located symmetrically,
which is a special case and does not cover all possible
combinations. Hence it is not sufficient to determine the
PZ of the ATR system of operating NPP. Computer
programs, for example, from “Primtech”, Pentair,
ERICO, Entegra, etc., are used to calculate the ATR PZ
of arbitrary heights and locations, but they are a
commercial secret of development companies and have
some remarks on the calculation results (namely, the
form of obtained PZ for lightning protection system).
Thus, the development of a mathematical apparatus
and engineering technique for calculating and
constructing a PZ for ATR system with complex
configuration using the rolling sphere method for
existing power energy objects, in particular NPP,
according to modern international standards (EN 62305-
3:2012) is the scientific and practical task of current
interest.
The aim of the work is a mathematical analysis of
the rolling sphere method to develop a model for
constructing protection zones of a complex system of
lightning conductors according to DSTU EN
62305:2012 for protection NPP objects against direct
lightning strike.
GENERAL ANALYSIS THE PROTECTION
ZONES OF THE AIR-TERMINATION ROD
AGAINST DIRECT LIGHTNING STRIKE
ACCORDING TO EN 62305-3:2012
The main method to determine the protection of
objects against direct lightning strike is the construction
of system ATR. In order to use the lightning protection
means (rod and catenary wire) more effectively, all
combinations of PZ should be most fully taken into
account, for which their mathematical description is
necessary. Normative base [3] provides only a general
idea of the external view of the PZ (geometry) for two
types (single rod and single catenary wire), which is not
enough for mathematical modeling of the lightning
protection system (multiple catenary wires and rods of
arbitrary height and location).
An analysis of the features of the normative base [2,
3] was carried out defining the following:
– the focus on graphical methods for PZ
constructing, which causes difficulties with a large
number of objects and ATRs, leads to the error
probability in geometric constructing and modeling, as
well as the interpretation of the results due to the
presence of a human factor;
– the lack of a mathematical description for the ATR
system, that does not allow in practice to carry out the
synthesis and optimization of a lightning protection
system.
Due to the presence of various configurations of the
lightning protection system at the NPP (double, multiple
unequal ATR, inclined catenary wires and their
combinations) it is advisable to use special software for
ATR PZ calculation, as indicated in [2, 3]. Therefore,
the relevance of creating such a software package comes
to the fore, for which you first need to create a
mathematical description that is absent in the current
normative base.
Therefore, it is possible to identify a number of basic
tasks that need to be solved for the design and analysis
of the lightning protection of NPP energy objects (open
switchgear, buildings and constructions) with an
arbitrary ATR configuration:
– creation of a mathematical description of the PZ for
all possible forms and types of ATR (rod and catenary
wires, single and multiple);
– development of techniques for assessing lightning
protection of objects by a complex of various ATRs
(any combinations of ATRs and buildings without
limiting their number);
– development of techniques for determining the
optimal system of lightning protection for a complex of
objects using various types of ATRs;
– creation of software products for calculations
(design and analysis) of lightning protection systems.
Since the standard [3] gives only a general view of
the obtained PZ, there is a need to develop a universal
technique for PZ constructing. To solve the problem of
constructing a ATR PZ for NPP using the rolling sphere
method it is necessary to perform its decomposition,
that is, to obtain a general solution it is necessary to
obtain the solution to a number of particular problems.
To do this, we construct a mathematical model for the
PZ of the single and double ATR.
MATHEMATICAL MODEL OF THE
PROTECTION ZONE OF SINGLE
AIR-TERMINATION ROD
In the task of constructing a joint PZ, a model of a
single ATR zone is a special case, since it is more
common to consider a model with more than two ATRs.
For the basis we use solutions of similar problems,
considered in [8].
Consider the geometric interpretation of this
problem. Fig. 1 shows the vertical and horizontal
section for PZ of single ATR.
Geometric model in Fig. 1 is constructed on the
basis of the ratio of the ATR height and a given level of
lightning protection. The purpose of PZ model
constructing is to find the coordinates of the points
forming its zone in the space (xi, yi, zi). For this you
need to:
– find the height of PZ (zi) for known xi and yi;
– determine the radius of the projection circle of the
sphere on the soil plane.
To determine the coordinates xi, yi, zi of any point in
the zone, we write the equation of the sphere, which
touches the ATR and the soil:
22)(2)(2)(
S
Rczbyax ,
where a, b, c are coordinates of the sphere center; RS is
the sphere radius, which is determined by the level of
lightning protection (20, 30, 45 or 60 m) [3].
Object
RS
Rt
ATR
I (XI; YI; ZI)
HATR
Fig. 1. PZ of a single ATR
Let the coordinates xi, yi of some point I be given
and it is necessary to find the coordinate zi of this point
belonging to the surface of PZ. Let's calculate the
distance from this point to ATR (Rt). Then we get:
2)(2)( iymyixmxtR , (1)
where xm, ym are coordinates of ATR location.
Let's calculate the radius of the circle of the sphere
projection on the soil plane:
,for ,
,for ,2)(2
SRATRHSRR
SRATRHATRHSRSRR
(2)
where HATR is the ATR height.
Then for Rt < R we get:
2)(2
tRR
S
R
S
RiZ . (3)
MATHEMATICAL MODEL OF THE
PROTECTION ZONE OF DOUBLE
AIR-TERMINATION ROD
As in the case of PZ constructing for a single ATR,
the task of obtaining a double ATR is a special case.
The geometric model is a problem of finding the
coordinates of the protection surface when the sphere
simultaneously touches two ATRs. Moreover, the
touching of the sphere occurs symmetrically with
respect to a straight line passing through the coordinates
of ATRs centers.
This task can be reduced to the following. Let it be
necessary to find a pair of intersection points P3 of two
circles formed by the projection of the sphere center on
the soil plane during the ATR breaking-in with a sphere
of a certain radius corresponding to the accepted level
of lightning protection. The geometrical interpretation is
shown in Fig. 2. That is, it is necessary to solve the
problem of finding the points located at a known
distance from a straight line. It is clear that there are two
such points (P3), and they are located symmetrically.
First we find the distance between the centers of the
circles d:
baPPd
01
.
b
a
h
r1
r0
P1 (x1; y1; z1)
P2 (x2; y2; z2)
P3 (x3; y3; z3)
P3 (x3; y3; z3)P0 (x0; y0; z0)
Fig. 2. To the definition of the sphere center, which
touches two ATRs
If
0 1
d r r ,
then there are no intersection points: the circles lie
separately. Similarly, in the case of
10
rrd
there are no solutions, since one circle is inside the
other. In such cases, there is a special case of single
ATR. In the case of contact of the circles, that is,
d = r0 + r1, then obviously a is equal to r0, and the
distance b = r1.
If
10
rrd , then we consider two right triangles:
∆P0P2P3 and ∆P1P2P3. We have:
.2
1
22
,2
0
22
rhb
rha
(4)
Having solved (4) for a, we get:
)2/()22
1
2
0
( ddrra .
Let's find the coordinates of the point P2 by writing
the equation of a straight line passing through the points
P0 and P1:
dxxaxx /)
01
(
02
,
dyyayy /)
01
(
02
.
Since the straight line passing through the points P3
and P2 is orthogonal to the straight line passing through
the points P0 and P1, the coordinates of P3 can be found
as follows:
dyyhxx /)
01
(
23
,
dxxhyy /)
01
(
23
,
S
Rz
3
.
Next, to build the PZ of double ATR, we will
consider the geometric model shown in Fig. 3. Points A1
and A2 are the centers of the sphere projection on the
soil if it touches both lightning conductors.
Let the coordinates xi, yi of a certain point in the
Cartesian coordinate system be given, find the
coordinate zi of this point belonging to the PZ surface.
According to the geometric model, if a point belongs to
the region A or the region B, then the coordinate zi is
determined by the expressions (1)–(3).
If the point belongs to the zone A1 or A2, then the
coordinate zi is defined as follows:
2
3
2
3
2 )()( yyxxRRz iiSSi . (5)
Thus, in contrast to the results given in [8], the
solution was obtained for calculating the PZ for the
system of two ATR of arbitrary height (see Fig. 3).
d
A1 Zone B
ATR1
Object
ATR2
A2
Zone A1
Zone A2
Object
ATR1
ATR2
Zone A
RS
r0 r1
Fig. 3. PZ of double ATR
MATHEMATICAL MODEL
OF PROTECTION ZONE WITH COMPLEX
CONFIGURATION OF ATR LOCATION
The special cases considered above make it possible
to construct a PZ of ATRs, when the ratio of heights,
distances between ATR and a given level of lightning
protection do not form a complex configuration of PZ of
these ATRs. However, in most cases, in particular at
NPP, a combination of dozens of unequal high ATRs
located at different distances from each other leads to
the formation of a complex PZ surface. To solve this
problem it is necessary to solve a number of subtasks:
– to determine the minimum number of ATRs
required to construct the PZ with a complex
configuration of the ATR location on the object's
scheme and to create a mathematical model to construct
such a PZ;
– to determine the number of ATRs involved in the
constructing of a joint PZ, for a given level of lightning
protection;
– to make an algorithm for constructing a joint PZ,
based on the ATRs location on the scheme and the
mathematical description for a specific ATR
configuration;
– to construct the geometric and mathematical model
for the selected ATR configuration.
CONCLUSIONS
1. The normative requirements for lightning
protection of nuclear power plant in Ukraine are
analyzed. The problems that arose in determining the
PZ of a lightning protection system with complex
configuration using harmonized DSTU EN 62305-
3:2012 are justified.
2. It is proposed to develop a technique for
constructing the PZ of a lightning protection system
based on the rolling sphere method using the
decomposition method. For this purpose, mathematical
models have been developed for calculating PZ for
single and double ATR of arbitrary height and location.
3. The research directions have been formed and the
ways of their solution have been proposed for the
development of a mathematical model of the PZ for a
system of rod lightning conductors of arbitrary
configuration and location.
REFERENCES
1. M.M. Rezinkina. Technique for predicting the
number of lightning strokes to extended objects //
Technical Physics. 2008, v. 53, N 5, p. 533-539.
2. DSTU B V.2.5-38:2008. Inzhenerne
obladnannya budynkiv i sporud. Ulashtuvannya
blyskavkozakhystu budivel' i sporud (IEC 62305:2006
NEC). Vved. 01.01.2009. K.: “Minrehionbud
Ukrayiny”, 2008. 63 p. (in Ukrainian).
3. EN 62305-3:2011. Protection against lightning –
Part 3: Physical damage to structures and life hazard.
4. E.M. Bazelyan. Rationing of lightning protection
in Russia. Main problems and ways of improvement //
III Russian conference on lightning protection, Saint
Petersburg, 2012, p. 372-382.
5. V.I. Komarov. On the question of the external
lightning protection system designing rolling sphere
method // Naukovij oglad. 2014, N 3(4), p. 100-105 (in
Ukrainian).
6. K.L.V. Dung. Lightning protection systems
design for substations by using masts and Matlab //
International Journal of Mathematical, Computational,
Physical, Electrical and Computer Engineering. 2010,
v. 4, N 5, p. 562-566,
7. G. Berger. Recent considerations on a 3D
electrogeometric model and its applications to the PIC
DU MIDI // V International conference on lightning
protection, St.-Peterburg, May, 2016.
8. Nit Petcharaks. Lightning protection zone in
substation using mast // KKU Engineering Journal.
2013, N 40(1), p. 11-20.
Article received 08.07.2019
ПРОБЛЕМАТИКА ПОСТРОЕНИЯ ЗОН ЗАЩИТЫ ДЛЯ АТОМНЫХ ЭЛЕКТРИЧЕСКИХ
СТАНЦИЙ УКРАИНЫ ПО СТАНДАРТУ EN 62305
А.Е. Истомин, Д.Г. Колиушко, С. В. Киприч, С.С. Руденко
Выполнен математический анализ метода катящейся сферы, для разработки модели построения зон
защиты сложной системы молниеотводов согласно ДСТУ EN 62305: 2012 для защиты объектов атомных
электрических станций от прямого удара молнии. Показана необходимость разработки соответствующей
математической модели для подобных объектов и предложены направление реализации с помощью метода
декомпозиции. Разработаны математические модели для расчета зон защиты одиночного и двойного
стержневых молниеотводов произвольной высоты и расположения. Сформированы направления для
дальнейших исследований.
ПРОБЛЕМАТИКА ПОБУДОВИ ЗОН ЗАХИСТУ БЛИСКАВКОВІДВОДІВ ДЛЯ АТОМНИХ
ЕЛЕКТРИЧНИХ СТАНЦІЙ УКРАЇНИ ЗА СТАНДАРТОМ EN 62305
О.Є. Істомін, Д.Г. Коліушко, С.В. Кіприч, С.С. Руденко
Виконано математичний аналіз методу сфери, що котиться, для розробки моделі побудови зон захисту
складної системи блискавковідводів згідно з ДСТУ EN 62305:2012 для захисту об’єктів атомних
електричних станцій від прямого удару блискавки. Показана необхідність розробки відповідної
математичної моделі для подібних об’єктів та запропоновано напрямок її реалізації за допомогою методу
декомпозиції. Розроблено математичні моделі для розрахунку зон захисту одиничного та подвійного
стрижньових блискавковідводів довільної висоти і розташування. Сформовано напрями подальших
досліджень.
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